EPITHELIAL-CELL SHEDDING IN ACUTE RENAL INJURY

1. To address the postulate that sublethally injured tubular cells may be shed from renal epithelium while still viable, studies mere undert aken in vivo in human 'acute tubular necrosis' and in rabbit models of renal tubular injury. 2. Substantial numbers of viable tubular cells were voided in the urine. When placed in culture, these cells gave ris e to monolayers, confirming viability. The majority of intact cells de monstrated markers of proximal tubule. 3. In vitro studies of human re nal proximal tubular cells exposed to hypoxia/anoxia showed rounding a nd retraction associated with disruption of actin microfilaments. Phal loidin stabilized the filaments and prevented the changes in cell shap e indicative of altered adherence.